Oscillator: Difference between revisions
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{{Glossary}} | {{Glossary}} | ||
An '''oscillator''' is a [[pattern]] that is a [[predecessor]] of itself. That is, it is a pattern that repeats itself after a fixed number of [[generation]]s (known as its [[period]]). The term is usually restricted to finite patterns that are not [[still life]]s, though still lifes may be thought of as oscillators with period 1. An oscillator is divided into a [[rotor]] and a [[stator]]. | An '''oscillator''' is a [[pattern]] that is a [[predecessor]] of itself. That is, it is a pattern that repeats itself after a fixed number of [[generation]]s (known as its [[period]]). The term is usually restricted to finite patterns that are not [[still life]]s, though still lifes may be thought of as oscillators with period 1. An oscillator is divided into a [[rotor]] (the individual [[cell]]s that actually oscillate) and a [[stator]] (the cells which remain alive throughout its whole period). | ||
[[Cellular automaton]] theory recognizes shift periodicity, which refers to a configuration reappearing in shifted form after a lapse of one or more generations. Without the shift, it is an oscillator, but if it moves it would be called a [[spaceship]]. | |||
==Important oscillators by period== | == Important oscillators by period == | ||
A list of the first-discovered oscillator of each period, as well the current smallest-known oscillator of that period, is provided here. Note that only [[ | A list of the first-discovered oscillator of each period,<ref>{{CiteHickersonOscillators|accessdate=April 11, 2009}}</ref> as well the current smallest-known oscillator of that period,<ref name="post132979" /> is provided here. Note that only non-trivial oscillators are considered here, in the sense that there must be at least one cell that oscillates at the full period (i.e. the overall pattern must have a nonzero [[strict volatility]]). In some cases, it is not known for certain what the first-discovered oscillator of a given period is, and in such situations all possible candidates are listed. | ||
< | For any period 59 or greater an oscillator can be constructed using the Herschel track method. In April, {{year|2013}} [[Mike Playle]] found a small 90-degree [[stable reflector]] known as the [[Snark]] that allows oscillators of all periods 43 or greater to be constructed. Since {{year|2023}}, oscillators of all periods less than 43 have been known showing that Life is [[omniperiodic]]. | ||
{| class="wikitable" | |||
The lowest population for which an infinite number of non-trivial oscillators are known to exist is 29, as two 12-cell pentadecathlons can reflect a 5-cell glider back and forth indefinitely in the correct position. The smallest example of this is the [[p60 glider shuttle]], with period-180, 300, and all other periods of the form 120n+60 possible with no extra cells required. 29 is conjectured to be the lowest population for which an infinite number of distinct non-trivial oscillators exist.<ref name="post180140"/> | |||
{| class="sortable wikitable" style="margin-left:auto;margin-right:auto;" | |||
! Period | ! Period | ||
! First discovered | ! First discovered | ||
! Discoverer | ! Discoverer | ||
! Year of discovery | ! Year of discovery | ||
! class=unsortable| | |||
! Smallest known | |||
! Minimum # of cells | |||
|- | |- | ||
! [[ | ! {{period|2|brief}} | ||
| [[blinker]] | |||
|[[John Conway]] | |||
| {{year|1969}} | |||
| rowspan="500" style="border: none;" | | |||
| [[blinker]] | | [[blinker]] | ||
| | | {{cells|3}} | ||
|- | |- | ||
! | ! {{period|3|brief}} | ||
| [[pulsar]] | | [[pulsar]] | ||
| John Conway | |John Conway | ||
| | | 1970 | ||
| [[caterer]] | |||
| {{cells|12}} | |||
|- | |- | ||
! | ! {{period|4|brief}} | ||
| | | [[pinwheel]] | ||
| | |[[Simon Norton]] | ||
| [[ | | 1970 | ||
| [[mazing]], [[mold]] | |||
| {{cells|12}} | |||
|- | |- | ||
! | ! {{period|5|brief}} | ||
| [[octagon 2]] | | [[octagon 2]] | ||
| [[ | |[[Sol Goodman]], [[Arthur Taber]] | ||
| [[ | | {{year|1971}} | ||
| [[pseudo-barberpole]] | |||
| {{cells|15}} | |||
|- | |- | ||
! | ! {{period|6|brief}} | ||
| | | [[$rats]] | ||
| [[ | |[[David Buckingham]] | ||
| [[ | | {{year|1972}} | ||
| [[unix]] | |||
| {{cells|16}} | |||
|- | |- | ||
! | ! {{period|7|brief}} | ||
| | | [[burloaferimeter]] | ||
| David Buckingham | |David Buckingham | ||
| 1972 | | 1972 | ||
| [[28P7.1]], [[28P7.2]], [[28P7.3]], [[burloaferimeter]] | |||
| {{cells|28}} | |||
|- | |- | ||
! | ! {{period|8|brief}} | ||
| [[figure eight]] | | [[figure eight]] | ||
| | |Simon Norton | ||
| 1970 | | 1970 | ||
| [[figure eight]] | |||
| {{cells|12}} | |||
|- | |||
! {{period|9|brief}} | |||
| [[worker bee]] | |||
|David Buckingham | |||
| 1972 | |||
| [[29P9]] | |||
| {{cells|29}} | |||
|- | |||
! {{period|10|brief}} | |||
| [[42P10.3]] | |||
|David Buckingham | |||
| data-sort-value="1976"|≤{{year|1976}} | |||
| [[24P10]] | |||
| {{cells|24}} | |||
|- | |||
! {{period|11|brief}} | |||
| [[38P11.1]] | |||
|David Buckingham | |||
| {{year|1977}} | |||
| [[rattlesnake]], [[diamondback]] | |||
| {{cells|33}} | |||
|- | |||
! {{period|12|brief}} | |||
| [[dinner table]] | |||
|[[Robert Wainwright]] | |||
| {{year|1972}} | |||
| [[mold on fire-spitting]] | |||
| {{cells|31}} | |||
|- | |||
! {{period|13|brief}} | |||
| [[Buckingham's p13]] | |||
|David Buckingham | |||
| 1976 | |||
| [[Beluchenko's p13]] | |||
| {{cells|34}} | |||
|- | |||
! {{period|14|brief}} | |||
| [[tumbler]] | |||
|[[George Collins]] | |||
| 1970 | |||
| [[tumbler]] | |||
| {{cells|16}} | |||
|- | |||
! {{period|15|brief}} | |||
| [[pentadecathlon]] | |||
|John Conway | |||
| 1970 | |||
| [[pentadecathlon]] | |||
| {{cells|12}} | |||
|- | |||
! {{period|16|brief}} | |||
| [[two pre-L hasslers]] | |||
|Robert Wainwright | |||
| {{year|1983}} | |||
| [[Rob's p16]] | |||
| {{cells|21}} | |||
|- | |||
! {{period|17|brief}} | |||
| [[54P17.1]] | |||
|[[Dean Hickerson]] | |||
| {{year|1997}} | |||
| [[honey thieves]] | |||
| {{cells|36}} | |||
|- | |||
! {{period|18|brief}} | |||
| [[117P18]]{{refn|group=note|name=lcm|[[Non-trivial]] oscillators of this period could have been constructed from two oscillators of lower period (usually [[sparker]]s), both of which were known by an earlier date. However, no such [[LCM oscillator]]s were attested prior to the discovery of this oscillator.}} | |||
|David Buckingham | |||
| data-sort-value="1991"|≤{{year|1991}} | |||
| [[p18 bi-block hassler]], [https://catagolue.hatsya.com/object?apgcode=xp18_wc93xs112ogggzbdhe96kk801zw1213&rule=b3s23 p18 phase shifter] | |||
| {{cells|43}} | |||
|- | |||
! {{period|19|brief}} | |||
| [[cribbage]] | |||
| [[Mitchell Riley]] | |||
| {{year|2023}} | |||
| [[cribbage]] | |||
| {{cells|92}} | |||
|- | |||
! {{period|20|brief}} | |||
| [[145P20]]{{refn|group=note|name=lcm}} | |||
|[[Noam Elkies]] | |||
| {{year|1995}} | |||
| [[mold on fumarole]] | |||
| {{cells|30}} | |||
|- | |||
! {{period|21|brief}} | |||
| [[124P21]]{{refn|group=note|name=lcm}} | |||
|Robert Wainwright | |||
| 1995 | |||
| [[32P21]] | |||
| {{cells|32}} | |||
|- | |||
! {{period|22|brief}} | |||
| [[168P22.1]] | |||
|Noam Elkies | |||
| 1997 | |||
| [[Jason's p22]] | |||
| {{cells|36}} | |||
|- | |||
! {{period|23|brief}} | |||
| [[David Hilbert]] | |||
|[[Luka Okanishi]], [[praosylen]] | |||
| {{year|2019}} | |||
| [[54P23]] | |||
| {{cells|54}} | |||
|- | |||
! {{period|24|brief}} | |||
| [[186P24]]{{refn|group=note|name=lcm}} | |||
|[[Bill Gosper]] | |||
| {{year|1994}} | |||
| [[caterer on figure eight]] | |||
| {{cells|24}} | |||
|- | |||
! {{period|25|brief}} | |||
| [[134P25]] | |||
|Noam Elkies | |||
| 1994 | |||
| [[30P25]] | |||
| {{cells|30}} | |||
|- | |||
! {{period|26|brief}} | |||
| [[p26 pre-pulsar shuttle]] | |||
|David Buckingham | |||
| 1983 | |||
| [[p26 honey farm hassler]] | |||
| {{cells|60}} | |||
|- | |||
! {{period|27|brief}} | |||
| [[123P27.1]] | |||
|Noam Elkies | |||
| {{year|2002}} | |||
| [[56P27]] | |||
| {{cells|56}} | |||
|- | |||
! {{period|28|brief}} | |||
| [[newshuttle]] | |||
|David Buckingham | |||
| {{year|1973}} | |||
| [[mold on 34P14 shuttle]] | |||
| {{cells|46}} | |||
|- | |||
! {{period|29|brief}} | |||
| [[p29 pre-pulsar shuttle]] | |||
|David Buckingham | |||
| {{year|1980}} | |||
| [[p29 pre-pulsar shuttle]] | |||
| {{cells|54}} | |||
|- | |||
! {{period|30|brief}} | |||
| [[queen bee shuttle]] | |||
|Bill Gosper | |||
| 1970 | |||
| [[queen bee shuttle]] | |||
| {{cells|20}} | |||
|- | |||
! {{period|31|brief}} | |||
| [[Merzenich's p31]] | |||
|[[Matthias Merzenich]] | |||
| {{year|2010}} | |||
| [[Merzenich's p31]] | |||
| {{cells|48}} | |||
|- | |||
! {{period|32|brief}} | |||
| [[gourmet]] | |||
|David Buckingham | |||
| {{year|1978}} | |||
| [[p32 honey farm hassler]] | |||
| {{cells|45}} | |||
|- | |||
! {{period|33|brief}} | |||
| [[258P3 on Achim's p11]] | |||
|Noam Elkies, [[Achim Flammenkamp]] | |||
| 1997 | |||
| [[caterer on rattlesnake]] | |||
| {{cells|46}} | |||
|- | |||
! {{period|34|brief}} | |||
| [[74P34]] | |||
|[[Mitchell Riley]] | |||
| 2022 | |||
| [[74P34]] | |||
| {{cells|74}} | |||
|- | |||
! {{period|35|brief}} | |||
| [[p35 beehive hassler]]{{refn|group=note|name=lcm}} | |||
|Dean Hickerson | |||
| 1995 | |||
| [[p35 honey farm hassler]] | |||
| {{cells|44}} | |||
|- | |||
! {{period|36|brief}} | |||
| [[p36 toad hassler]]{{refn|group=note|name=lcm}} | |||
|Robert Wainwright | |||
| 1984 | |||
| [[22P36]] | |||
| {{cells|22}} | |||
|- | |||
! {{period|37|brief}} | |||
| [[Beluchenko's p37]] | |||
|[[Nicolay Beluchenko]] | |||
| {{year|2009}} | |||
| [[58P37]] | |||
| {{cells|58}} | |||
|- | |||
! {{period|38|brief}} | |||
| [[44P38]] | |||
|[[David Raucci]] | |||
| {{year|2022}} | |||
| [[42P38]] | |||
| {{cells|42}} | |||
|- | |||
! {{period|39|brief}} | |||
| [[134P39.1]] | |||
|Noam Elkies, David Buckingham | |||
| {{year|2000}} | |||
| [[caterer on Beluchenko's p13]] | |||
| {{cells|46}} | |||
|- | |||
! {{period|40|brief}} | |||
| [[p40 B-heptomino shuttle]]{{refn|group=note|name=lcm}} | |||
|David Buckingham | |||
| 1991 | |||
| [[Beluchenko's p40]] | |||
| {{cells|26}} | |||
|- | |||
! {{period|41|brief}} | |||
| [[208P41]] | |||
|Nora Brown | |||
| 2023 | |||
| [[p41 pi-heptomino hassler]] | |||
| {{cells|170}} | |||
|- | |||
! {{period|42|brief}} | |||
| [[p42 glider shuttle]]{{refn|group=note|name=lcm}} | |||
|Noam Elkies | |||
| 1994 | |||
| [[unix on 34P14 shuttle]] | |||
| {{cells|50}} | |||
|- | |||
! {{period|43|brief}} | |||
| [[p43 Snark loop]] | |||
|[[Mike Playle]] | |||
| {{year|2013}} | |||
| [[p43 pi-heptomino hassler]]<ref>{{LinkForumThread|format=ref|p=153483|title=Re: Oscillator Discussion Thread}}</ref> | |||
| {{cells|70}} | |||
|- | |||
! {{period|44|brief}} | |||
| [[p44 pi-heptomino hassler]] | |||
|David Buckingham | |||
| 1992 | |||
| [[mold on rattlesnake]] | |||
| {{cells|45}} | |||
|- | |||
! {{period|45|brief}} | |||
| [[pentadecathlon on snacker]] | |||
| [[Mark Niemiec]], John Conway | |||
| data-sort-value="1992"|≤1992 | |||
| [[p45 pi-heptomino hassler]] | |||
| {{cells|29}} | |||
|- | |||
! {{period|46|brief}} | |||
| [[twin bees shuttle]] | |||
|Bill Gosper | |||
| 1971 | |||
| [[twin bees shuttle]] | |||
| {{cells|28}} | |||
|- | |||
! {{period|47|brief}} | |||
| [[p47 pre-pulsar shuttle]] | |||
|David Buckingham | |||
| {{year|1982}} | |||
| [[p47 pre-pulsar shuttle]] | |||
| {{cells|84}} | |||
|- | |||
! {{period|48|brief}} | |||
| [[p48 toad hassler]] | |||
|Bill Gosper | |||
| 1994 | |||
| [[unix on Charity's p16]] | |||
| {{cells|44}} | |||
|- | |||
! {{period|49|brief}} | |||
| [[p49 bouncer loop]] | |||
|Noam Elkies | |||
| {{year|1999}} | |||
| [[44P49]] | |||
| {{cells|44}} | |||
|- | |||
! {{period|50|brief}} | |||
| [[p50 glider shuttle]] | |||
|Dean Hickerson | |||
| 1992 | |||
| [[24P10 on 30P25]] | |||
| {{cells|58}} | |||
|- | |||
! {{period|51|brief}} | |||
| [[Beluchenko's p51]] | |||
|Nicolay Beluchenko | |||
| 2009 | |||
| [[Period-51 glider gun|capped p51 gun]] | |||
| {{cells|84}} | |||
|- | |||
! {{period|52|brief}} | |||
| [[Four eaters hassling lumps of muck]] | |||
|David Buckingham | |||
| 1977 | |||
| [[four eaters hassling lumps of muck]] | |||
| {{cells|35}} | |||
|- | |||
! {{period|53|brief}} | |||
| [[p53 Snark loop]] | |||
|Mike Playle | |||
| {{year|2013}} | |||
| [[94P53]] | |||
| {{cells|94}} | |||
|- | |||
! {{period|54|brief}} | |||
| [[p54 shuttle]] | |||
|David Buckingham | |||
| {{year|1973}} | |||
| [[43P54]] | |||
| {{cells|43}} | |||
|- | |||
! {{period|55|brief}} | |||
| [[p55 pre-pulsar hassler]] | |||
|David Buckingham | |||
| {{year|1986}} | |||
| [[pseudo-barberpole on rattlesnake]] | |||
| {{cells|49}} | |||
|- | |||
! {{period|56|brief}} | |||
| [[p56 B-heptomino shuttle]]{{refn|group=note|name=lcm}} | |||
|David Buckingham | |||
|data-sort-value="1991"| ≤1991 | |||
| [[p56 B-heptomino shuttle]] | |||
| {{cells|45}} | |||
|- | |||
! {{period|57|brief}} | |||
| [[p57 Herschel loop 1]] | |||
|[[Dietrich Leithner]] | |||
| 1997 | |||
| [[112P57]] | |||
| {{cells|112}} | |||
|- | |||
! {{period|58|brief}} | |||
| [[p58 toadsucker]] | |||
|Bill Gosper | |||
| 1994 | |||
| [[p58 pi-heptomino hassler]], {{LinkCatagolue|xp58_y932aczy5ooy3osogzyi76y0cczz33y06eggggy3ggzy5131y311zy9354c|patternname=54p58|style=raw}} | |||
| {{cells|54}} | |||
|- | |||
! {{period|59|brief}} | |||
| [[p59 Herschel loop 1]] | |||
|David Buckingham | |||
| 1997 | |||
| [[p59 pi-heptomino hassler]] | |||
| {{cells|86}} | |||
|- | |||
! {{period|60|brief}} | |||
| [[p60 glider shuttle]] | |||
| ? | |||
|data-sort-value="1971"| ≤1971 | |||
| [[mold on pentadecathlon]] | |||
| {{cells|24}} | |||
|- | |||
! {{period|61|brief}} | |||
| [[p61 Herschel loop 1]] | |||
|David Buckingham | |||
| {{year|1996}} | |||
| [[p61 pi-heptomino hassler]] | |||
| {{cells|134}} | |||
|- | |||
! {{period|62|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[66P62]] | |||
| {{cells|66}} | |||
|- | |- | ||
! | ! {{period|63|brief}} | ||
| | | Herschel loop | ||
| | | David Buckingham | ||
| [[ | | 1996 | ||
| | | [[64P63|32P21 phase-shifting p5]] | ||
{| | | {{cells|64}} | ||
|- | |- | ||
! Period | ! {{period|64|brief}} | ||
! | | Herschel loop | ||
! | | David Buckingham | ||
| 1996 | |||
| [[Merzenich's p64]] | |||
| {{cells|34}} | |||
|- | |||
! {{period|65|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[fumarole on Beluchenko's p13]] | |||
| {{cells|52}} | |||
|- | |||
! {{period|66|brief}} | |||
| [[p42 glider shuttle|p66 glider shuttle]] | |||
| Robert Wainwright | |||
| 1984 | |||
| [[caterer on Jason's p22]] | |||
| {{cells|48}} | |||
|- | |||
! {{period|67|brief}} | |||
| [[p67 Herschel loop|Herschel loop]] | |||
| David Buckingham | |||
| 1996 | |||
| [[p67 Snark loop]] | |||
| {{cells|228}} | |||
|- | |||
! {{period|68|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[p68 century hassler]] | |||
| {{cells|38}} | |||
|- | |||
! {{period|69|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[54P23#LCM oscillators|55P23 on Grin reagent weld loading dock]] | |||
| {{cells|103}} | |||
|- | |||
! {{period|70|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[fumarole on 34P14 shuttle]] | |||
| {{cells|52}} | |||
|- | |||
! {{period|71|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[p71 dependent reflector loop]] | |||
| {{cells|92}} | |||
|- | |||
! {{period|72|brief}} | |||
| [[two blockers hassling R-pentomino]] | |||
|Robert Wainwright | |||
| 1990 | |||
| [[figure eight on 22P36]] | |||
| {{cells|36}} | |||
|- | |||
! {{period|73|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[p73 lumps of muck hassler]] | |||
| {{cells|68}} | |||
|- | |||
! {{period|74|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[Raucci's p74]] | |||
| {{cells|84}} | |||
|- | |||
! {{period|75|brief}} | |||
| [[6 bits]] | |||
| Robert Wainwright | |||
| 1984 | |||
| [[pentadecathlon on 30P25]] | |||
| {{cells|42}} | |||
|- | |||
! {{period|76|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[p76 pi-heptomino shuttle]] | |||
| {{cells|52}} | |||
|- | |||
! {{period|77|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[34P7 on rattlesnake]] | |||
| {{cells|67}} | |||
|- | |||
! {{period|78|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[p6 thumb on Beluchenko's p13]] | |||
| {{cells|61}} | |||
|- | |||
! {{period|79|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[p79 pi-heptomino hassler]] | |||
| {{cells|80}} | |||
|- | |||
! {{period|80|brief}} | |||
| [[middleweight volcano]] on [[Achim's other p16]] | |||
| Dean Hickerson, Achim Flammenkamp | |||
| 1994 | |||
| [[fumarole on Rob's p16]] | |||
| {{cells|39}} | |||
|- | |||
! {{period|81|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| {{LinkCatagolue|xp81_yzyzwca23zyzyy33y2eu80gswsg0gzyzyw2a6y4178ewew121zyzyz0o4ozyzyugs26x1zyzyzxco4zyzyca64zzzyzyisg8zyu42ezzzyz08okzya86czyhoge2zyc696z0gxsws4oy5okgz1212ewe205vsy2ggzyaggkc011zya1|patternname=p81 180° glider loop|style=raw}} | |||
| {{cells|146}} | |||
|- | |||
! {{period|82|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[p82 lumps of muck hassler]] | |||
| {{cells|48}} | |||
|- | |||
! {{period|83|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[62P83]] | |||
| {{cells|62}} | |||
|- | |||
! {{period|84|brief}} | |||
| [[pi orbital]] | |||
| Noam Elkies | |||
| 1995 | |||
| [[p84 honey farm hassler]] | |||
| {{cells|42}} | |||
|- | |||
! {{period|85|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[p85 R-pentomino hassler]] | |||
| {{cells|68}} | |||
|- | |||
! {{period|86|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[76P86]] | |||
| {{cells|76}} | |||
|- | |||
! {{period|87|brief}} | |||
| p3 sparker on [[p29 pentadecathlon hassler]] | |||
| Bill Gosper | |||
| 1994 | |||
| [[84P87]] | |||
| {{cells|84}} | |||
|- | |||
! {{period|88|brief}} | |||
| p44n glider loop | |||
|David Buckingham | |||
| 1992 | |||
| [[figure eight on rattlesnake]] | |||
| {{cells|45}} | |||
|- | |||
! {{period|89|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| {{LinkCatagolue|xp89_yzy833y58e1e88gzyzyj330311ybckzyzyd3224e6y725acy165lozyzwgs2552ypggzyzy2gcoy1o8a6xca8y911zzzzysgy1g0gzy4ooy9153x6511y113xggzggyx4aa43z1qa6y135a4y767244cz023yag88c0cczye117871y5cc|patternname=transparent long boat glider loop|style=raw}} | |||
| {{cells|164}} | |||
|- | |||
! {{period|90|brief}} | |||
| p30n glider loop | |||
| ? | |||
| data-sort-value="1973"|≤1973 | |||
| [[unix on p45 pi-heptomino hassler]] | |||
| {{cells|45}} | |||
|- | |||
! {{period|91|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[34P7 on Beluchenko's p13]] | |||
| {{cells|68}} | |||
|- | |||
! {{period|92|brief}} | |||
| p46n glider loop | |||
| Bill Gosper | |||
| 1971 | |||
| [[mold on twin bees shuttle]] | |||
| {{cells|44}} | |||
|- | |||
! {{period|93|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[caterer on Merzenich's p31]] | |||
| {{cells|60}} | |||
|- | |||
! {{period|94|brief}} | |||
| capped [[P94S]] | |||
| Dean Hickerson | |||
| 1990 | |||
| [[54P94]] | |||
| {{cells|54}} | |||
|- | |||
! {{period|95|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[Cribbage#LCM oscillators|toaster variant on Cribbage]] | |||
| {{cells|137}} | |||
|- | |||
! {{period|96|brief}} | |||
| [[p96 Hans Leo hassler]] | |||
| Noam Elkies | |||
| 1995 | |||
| [[period-48 glider gun with boat-bit]] | |||
| {{cells|59}} | |||
|- | |||
! {{period|97|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| {{LinkCatagolue|xp97_ydg88e1u8y533z0kcyb11313kzol56y1ca52y6115137zy4ggyp2552sgzy411y94ocx6a8ozyzxe24zzzzyzy448ezyzyg32acx634y9ggzyzy4178kk8yp11zyzyksogkggy68ka6y1ckl3zyzyp5ogoggyb65zyzyeooy52fge221|patternname=transparent long boat glider loop|style=raw}} | |||
| {{cells|164}} | |||
|- | |||
! {{period|98|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[Gallus]], [https://catagolue.hatsya.com/object/xp98_660g0fmy64a4x62z0cqb0t53y8ca8x66w66zw6fx66ydccxuczxccwccyeokn0qb6zy6ccx4a4y6du010cc/b3s23 p98 glider shuttle] | |||
| {{cells|105}} | |||
|- | |||
! {{period|99|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[Rattlesnake#LCM oscillators|rattlesnake on 42P9]] | |||
| {{cells|75}} | |||
|- | |||
! {{period|100|brief}} | |||
| [[centinal]] | |||
|Bill Gosper | |||
|data-sort-value="1987"|≤1987 | |||
| [[mold on 30P25]] | |||
| {{cells|42}} | |||
|- | |||
! {{period|101|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[116P101]] | |||
| {{cells|116}} | |||
|- | |||
! {{period|102|brief}} | |||
| p102+18n [[traffic jam]] | |||
| Dean Hickerson | |||
| data-sort-value="1994"|1994 | |||
| [[Raucci's p102]] | |||
| {{cells|67}} | |||
|- | |||
! {{period|103|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[siffrin's p103]] | |||
| {{cells|68}} | |||
|- | |||
! {{period|104|brief}} | |||
| p100+4n [[traffic jam]] | |||
| Bill Gosper | |||
| 1994 | |||
| [[figure eight on Beluchenko's p13]] | |||
| {{cells|46}} | |||
|- | |||
! {{period|105|brief}} | |||
| [[pentadecathlon]] on [[44P7.2]] | |||
| ? | |||
|data-sort-value="1992"| ≤1992 | |||
| [[34P7]] on [[pentadecathlon]] | |||
| {{cells|46}} | |||
|- | |||
! {{period|106|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[66P106]] | |||
| {{cells|66}} | |||
|- | |||
! {{period|107|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[86P107]] | |||
| {{cells|86}} | |||
|- | |||
! {{period|108|brief}} | |||
| [[p54 shuttle]] on [[figure eight]] | |||
| ? | |||
|data-sort-value="1992"| ≤1992 | |||
| {{LinkCatagolue|xp108_8o6pajkk8z32q921y8ca23z321y1131y08c8zy0c453|patternname=22P36 phase-shifting p5|style=raw}} | |||
| {{cells|54}} | |||
|- | |||
! {{period|109|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[rectifier|p109 rectifier loop]] | |||
| {{cells|156}} | |||
|- | |||
! {{period|110|brief}} | |||
| [[p110 traffic jam]] | |||
| Bill Gosper | |||
| 1994 | |||
| [[pseudo-barberpole on Jason's p22]] | |||
| {{cells|51}} | |||
|- | |||
! {{period|111|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[fire-spitting on p37 lumps of muck hassler]] | |||
| {{cells|91}} | |||
|- | |||
! {{period|112|brief}} | |||
| p100+4n [[traffic jam]] | |||
| Bill Gosper | |||
| 1994 | |||
| [[tumbler on Rich's p16]] | |||
| {{cells|50}} | |||
|- | |||
! {{period|113|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[86P113]] | |||
| {{cells|86}} | |||
|- | |||
! {{period|114|brief}} | |||
| [[p42 glider shuttle|p66+24n glider shuttle]] | |||
| Robert Wainwright | |||
| 1984 | |||
| [[caterer on 42P38]] | |||
| {{cells|54}} | |||
|- | |||
! {{period|115|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| {{LinkCatagolue|xp115_y032acy0ezw6ioy2gy0c871zca16a4x317zy2o8a6y0gbbgn1e808ozya11mq0v5kk8zye343|patternname=92P115|style=raw}} | |||
| {{cells|92}} | |||
|- | |||
! {{period|116|brief}} | |||
| p4 sparker on [[p29 pentadecathlon hassler]] | |||
| Bill Gosper | |||
| 1994 | |||
| {{LinkCatagolue|xp116_y6o4an7zy711zy166y5ok4kozym31e8zx32acyc6a8oz2egozy535453y5cc|patternname=mold on p58 pi-heptomino hassler|style=raw}} | |||
| {{cells|68}} | |||
|- | |||
! {{period|117|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[Beluchenko's p13#LCM oscillators|Beluchenko's p13 on 42P9]] | |||
| {{cells|76}} | |||
|- | |||
! {{period|118|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[86P118]] | |||
| {{cells|86}} | |||
|- | |||
! {{period|119|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[72P119]] | |||
| {{cells|72}} | |||
|- | |||
! {{period|120|brief}} | |||
| p30n glider loop | |||
| ? | |||
| data-sort-value="1973"|≤1973 | |||
| [[figure eight on pentadecathlon]] | |||
| {{cells|24}} | |||
|- | |||
! {{period|122|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[R-pentomino hasslers#p122|p122 R-pentomino hassler]] | |||
| {{cells|102}} | |||
|- | |||
! {{period|123|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[R-pentomino hasslers#p123|p123 R-pentomino hassler]] | |||
| {{cells|116}} | |||
|- | |||
! {{period|124|brief}} | |||
| [[p124 lumps of muck hassler]] | |||
| Dean Hickerson | |||
| 1994 | |||
| [[mold on Merzenich's p31]] | |||
| {{cells|60}} | |||
|- | |||
! {{period|126|brief}} | |||
| p102+6n [[traffic jam]] | |||
| Noam Elkies | |||
| data-sort-value="1996"|≤1996 | |||
| [[R-pentomino hasslers#p126|p126 R-pentomino hassler]] | |||
| {{cells|52}} | |||
|- | |||
! {{period|127|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[74P127]] | |||
| {{cells|74}} | |||
|- | |||
! {{period|128|brief}} | |||
| [[Period-256 glider gun#Gallery|spark-assisted p128 Herschel loop]] | |||
| David Buckingham | |||
| 1991 | |||
| [[60P128]] | |||
| {{cells|60}} | |||
|- | |||
! {{period|129|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[p129 R-pentomino hassler]] | |||
| {{cells|38}} | |||
|- | |||
! {{period|130|brief}} | |||
| [[p50 glider shuttle|p50+40n glider shuttle]] | |||
| Dean Hickerson | |||
| 1992 | |||
| {{LinkCatagolue|xp130_x32acz31e88g0653zy01pgz66w1023z66w8gkcy2o62453zy08py532156zc8711w6aczxc453|patternname=fumarole on 70P26|style=raw}} | |||
| {{cells|88}} | |||
|- | |||
! {{period|132|brief}} | |||
| p44n glider loop | |||
| David Buckingham | |||
| 1992 | |||
| [[mold on Jason's p33]] | |||
| {{cells|72}} | |||
|- | |||
! {{period|133|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[B-heptomino hasslers#p133|p133 B-heptomino hassler]] | |||
| {{cells|84}} | |||
|- | |||
! {{period|135|brief}} | |||
| [[106P135]] | |||
| Bill Gosper | |||
| {{year|1989}} | |||
| [[pentadecathlon on 56P27]] | |||
| {{cells|68}} | |||
|- | |||
! {{period|136|brief}} | |||
| p136 spark-assisted Herschel loop | |||
| David Buckingham | |||
| 1991 | |||
| {{LinkCatagolue|xp136_y6rb8oz0oggyhssszx23y56c53y6777zgs26zyf354c|patternname=figure eight on p68 century hassler|style=raw}} | |||
| {{cells|50}} | |||
|- | |||
! {{period|138|brief}} | |||
| p46n glider loop | |||
| Bill Gosper | |||
| 1971 | |||
| [[Gabriel's p138]] | |||
| {{cells|36}} | |||
|- | |||
! {{period|140|brief}} | |||
| p100+10n traffic jam | |||
| Bill Gosper | |||
| 1994 | |||
| [[p140 two-glider octomino hassler]] | |||
| {{cells|58}} | |||
|- | |||
! {{period|141|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[fire-spitting on p47 pre-pulsar shuttle]] | |||
| {{cells|103}} | |||
|- | |||
! {{period|143|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| {{LinkCatagolue|xp143_xgbb88gzy1cd3gv04aczc4530gy1gr3zy1d5a64210g8c4066zy7kr6og|patternname=p11 thumb on Beluchenko's p13|style=raw}} | |||
| {{cells|69}} | |||
|- | |||
! {{period|144|brief}} | |||
| capped p144 [[gunstar]] | |||
| David Buckingham | |||
| 1990 | |||
| [[Achim's p144]] | |||
| {{cells|42}} | |||
|- | |||
! {{period|146|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[p146 pi-heptomino hassler]] | |||
| {{cells|51}} | |||
|- | |||
! {{period|150|brief}} | |||
| p30n glider loop | |||
| ? | |||
| data-sort-value="1973"|≤1973 | |||
| [[unix on 30P25]] | |||
| {{cells|46}} | |||
|- | |||
! {{period|152|brief}} | |||
| p136+8n Herschel loop | |||
| David Buckingham | |||
| 1991 | |||
| [[42P38#LCM oscillators|figure eight on 42P38]] | |||
| {{cells|54}} | |||
|- | |||
! {{period|156|brief}} | |||
| p152+4n Herschel loop | |||
| David Buckingham | |||
| 1991 | |||
| {{LinkCatagolue|xp156_og8o0e93y266zx32wom5hley266zy312221y466zya6a8o033dew66|patternname=unix on p52 LOM hassler|style=raw}} | |||
| {{cells|66}} | |||
|- | |||
! {{period|158|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[Pi-heptomino hasslers#p158|p158 pi-heptomino hassler]] | |||
| {{cells|96}} | |||
|- | |||
! {{period|160|brief}} | |||
| p136+8n Herschel loop | |||
| David Buckingham | |||
| 1991 | |||
| [[Pi-heptomino hasslers#p160|p160 pi-heptomino hassler]] | |||
| {{cells|56}} | |||
|- | |||
! {{period|165|brief}} | |||
| [[p165 glider shuttle]] | |||
| Robert Wainwright | |||
| data-sort-value="1989"|≤1989 | |||
| [[rattlesnake on pentadecathlon]] | |||
| {{cells|45}} | |||
|- | |||
! {{period|166|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[R-pentomino hasslers#p166|p166 R-pentomino hassler]] | |||
| {{cells|102}} | |||
|- | |||
! {{period|171|brief}} | |||
| p150+3n Herschel loop | |||
| David Buckingham | |||
| 1991 | |||
| [[Pi-heptomino hasslers#p171|p171 pi-heptomino hassler]] | |||
| {{cells|128}} | |||
|- | |||
! {{period|177|brief}} | |||
| p150+3n Herschel loop | |||
| David Buckingham | |||
| 1991 | |||
| [[Karel's p177]], [[Caterer]] on [[92P59]]<ref name="post163608"/> | |||
| {{cells|104}} | |||
|- | |||
! {{period|187|brief}} | |||
| Herschel loop | |||
| David Buckingham | |||
| 1996 | |||
| [[Century hasslers#p187|p187 century hassler]] | |||
| {{cells|112}} | |||
|- | |||
! {{period|188|brief}} | |||
| p94n glider loop | |||
| Dean Hickerson | |||
| 1990 | |||
| {{LinkCatagolue|xp188_y8o8y1ca23zyj66zxooy4eoiczzydo4coy4ccz695qsoxggy3101zy511w8oy18czy7311|patternname=mold on 54P94|style=raw}} | |||
| {{cells|68}} | |||
|- | |||
! {{period|192|brief}} | |||
| p136+8n Herschel loop | |||
| David Buckingham | |||
| 1991 | |||
| [[57P192]] | |||
| {{cells|57}} | |||
|- | |||
! {{period|196|brief}} | |||
| p152+4n Herschel loop | |||
| David Buckingham | |||
| 1991 | |||
| [[44P49#LCM_oscillators|mold on 44P49]] | |||
| {{cells|56}} | |||
|- | |- | ||
! | ! {{period|199|brief}} | ||
| | | Herschel loop | ||
| [[ | | David Buckingham | ||
| 1996 | |||
| [[84P199]] | |||
| {{cells|84}} | |||
|- | |- | ||
! | ! {{period|200|brief}} | ||
| [[ | | p100n glider loop | ||
| | | Bill Gosper | ||
| data-sort-value="1987"|≤1987 | |||
| [[figure eight on 30P25]] | |||
| {{cells|42}} | |||
|- | |- | ||
! | ! {{period|201|brief}} | ||
| [[ | | p150+3n Herschel loop | ||
| | | David Buckingham | ||
| 1991 | |||
| Capped [[period-201 glider gun]] | |||
| {{cells|98}} | |||
|- | |- | ||
! | ! {{period|220|brief}} | ||
| [[ | | p152+4n Herschel loop | ||
| | | David Buckingham | ||
| 1991 | |||
| [[p220 honey farm shuttle]] | |||
| {{cells|74}} | |||
|- | |- | ||
! | ! {{period|226|brief}} | ||
| [[ | | Herschel loop | ||
| | | David Buckingham | ||
| 1996 | |||
| {{LinkCatagolue|xp226_yfbdz8oy633z0123zyfggy166zy9ss8x1409cwcczyb33zy9oowo80gx3bsszy9ggx2046zy911zyx31e8zygo8y133zyg23|patternname=Boat-bitted|style=raw}} [[86P113]] | |||
| {{cells|84}} | |||
|- | |- | ||
! | ! {{period|232|brief}} | ||
| [[ | | [[figure eight on p29 pre-pulsar shuttle]] | ||
| | | ? | ||
| data-sort-value="9999"|? | |||
| [[figure eight on p29 pre-pulsar shuttle]] | |||
| {{cells|66}} | |||
|- | |- | ||
! | ! {{period|246|brief}} | ||
| | | [[p42 glider shuttle#Gallery|p246 glider shuttle]] | ||
| | | Dean Hickerson | ||
| 1992 | |||
| [[unix]] on [[p82 lumps of muck hassler]] | |||
| {{cells|64}} | |||
|- | |- | ||
! | ! {{period|256|brief}} | ||
| | | [[Period-256 glider gun#Gallery|spark-assisted p256 Herschel loop]] | ||
| [[ | | David Buckingham | ||
| 1991 | |||
| [[86P256]] | |||
| {{cells|86}} | |||
|- | |- | ||
! | ! {{period|312|brief}} | ||
| [[ | | p136+8n Herschel loop | ||
| | | David Buckingham | ||
| 1991 | |||
| [[60P312]] | |||
| {{cells|60}} | |||
|- | |- | ||
! | ! {{period|368|brief}} | ||
| [[ | | p46n glider loop | ||
| | | Bill Gosper | ||
| 1971 | |||
| [[period-184 glider gun with boat-bits]] | |||
| {{cells|48}} | |||
|- | |- | ||
! | ! {{period|384|brief}} | ||
| [[ | | p136+8n Herschel loop | ||
| | | David Buckingham | ||
| 1991 | |||
| [[49P384]] | |||
| {{cells|49}} | |||
|- | |- | ||
! | ! {{period|492|brief}} | ||
| [[ | | p150+3n Herschel loop | ||
| | | David Buckingham | ||
| 1991 | |||
| [[period-246 glider gun with boat-bit]] | |||
| {{cells|87}} | |||
|- | |- | ||
! | ! {{period|856|brief}} | ||
| | | capped [[period-856 glider gun]] | ||
| [[ | | David Buckingham | ||
| 1991 | |||
| p856 glider shuttle <!-- same as 128, 136, and 256, but Catagolue won't recognize it--> | |||
| {{cells|92}} | |||
|} | |} | ||
</ | |||
==Notes== | |||
<references group=note /> | |||
==References== | |||
<references> | |||
<ref name="post132979">{{LinkForumThread | |||
|format = ref | |||
|title = Re: Smallest Known Oscillators to p106 (and Beyond) | |||
|p = 132979 | |||
|author = Jeremy Tan | |||
|date = July 3, 2021 | |||
}}</ref> | |||
<ref name="post163608">{{LinkForumThread | |||
|format = ref | |||
|title = Re: Smallest Known Oscillators to p106 (and Beyond) | |||
|p = 163608 | |||
|author = Period1GliderGun | |||
|date = July 12, 2023 | |||
}}</ref> | |||
<ref name="post180140">{{LinkForumThread | |||
|format = ref | |||
|title = Re: Unproven conjectures | |||
|p = 180140 | |||
|author = Connor Steppie | |||
|date = March 13, 2024 | |||
}}</ref> | |||
</references> | |||
==See also== | ==See also== | ||
*[[List of common oscillators]] | * [[List of common oscillators]] | ||
*[[: | * {{CategoryLink|Flipping oscillators}} | ||
*[[ | * {{CategoryLink|Oscillators}} | ||
* [[Omniperiodic]] | |||
* [[Table of oscillators by period]] | |||
* [[Prime-period oscillator]]s | |||
* [[LifeWiki:Game_of_Life_Status_page#Oscillator_periods|Oscillator periods status table]] | |||
* [[Almost oscillator]] | |||
* [[Oscillizer]] - analyze and get vital statistics for an oscillator | |||
==External links== | ==External links== | ||
* | * {{LinkWikipedia|Oscillator_(cellular_automaton)}} | ||
* {{LinkLexicon|lex_o.htm#oscillator}} | |||
* {{LinkLexicon|lex_f.htm#flipper|name=Flipper}} | |||
===Forum threads=== | |||
* {{LinkForumThread|f=2|t=1437|title=Oscillator Discussion Thread}} | |||
* {{LinkForumThread|f=2|t=5338|title=Smallest Known Oscillators to p106 (and Beyond)}} | |||
* {{LinkForumThread|f=7|t=5351|title=First Known Oscillators for Each Period}} | |||
__NOTOC__ | |||
Latest revision as of 16:43, 23 March 2026
An oscillator is a pattern that is a predecessor of itself. That is, it is a pattern that repeats itself after a fixed number of generations (known as its period). The term is usually restricted to finite patterns that are not still lifes, though still lifes may be thought of as oscillators with period 1. An oscillator is divided into a rotor (the individual cells that actually oscillate) and a stator (the cells which remain alive throughout its whole period).
Cellular automaton theory recognizes shift periodicity, which refers to a configuration reappearing in shifted form after a lapse of one or more generations. Without the shift, it is an oscillator, but if it moves it would be called a spaceship.
Important oscillators by period
A list of the first-discovered oscillator of each period,[1] as well the current smallest-known oscillator of that period,[2] is provided here. Note that only non-trivial oscillators are considered here, in the sense that there must be at least one cell that oscillates at the full period (i.e. the overall pattern must have a nonzero strict volatility). In some cases, it is not known for certain what the first-discovered oscillator of a given period is, and in such situations all possible candidates are listed.
For any period 59 or greater an oscillator can be constructed using the Herschel track method. In April, 2013 Mike Playle found a small 90-degree stable reflector known as the Snark that allows oscillators of all periods 43 or greater to be constructed. Since 2023, oscillators of all periods less than 43 have been known showing that Life is omniperiodic.
The lowest population for which an infinite number of non-trivial oscillators are known to exist is 29, as two 12-cell pentadecathlons can reflect a 5-cell glider back and forth indefinitely in the correct position. The smallest example of this is the p60 glider shuttle, with period-180, 300, and all other periods of the form 120n+60 possible with no extra cells required. 29 is conjectured to be the lowest population for which an infinite number of distinct non-trivial oscillators exist.[3]
Notes
References
- ↑ Dean Hickerson's oscillator stamp collection. Retrieved on April 11, 2009.
- ↑ Jeremy Tan (July 3, 2021). Re: Smallest Known Oscillators to p106 (and Beyond) (discussion thread) at the ConwayLife.com forums
- ↑ Connor Steppie (March 13, 2024). Re: Unproven conjectures (discussion thread) at the ConwayLife.com forums
- ↑ Re: Oscillator Discussion Thread (discussion thread) at the ConwayLife.com forums
- ↑ Period1GliderGun (July 12, 2023). Re: Smallest Known Oscillators to p106 (and Beyond) (discussion thread) at the ConwayLife.com forums
See also
- List of common oscillators
- Flipping oscillators (category)
- Oscillators (category)
- Omniperiodic
- Table of oscillators by period
- Prime-period oscillators
- Oscillator periods status table
- Almost oscillator
- Oscillizer - analyze and get vital statistics for an oscillator
External links
- Oscillator at Wikipedia
- Oscillator at the Life Lexicon
- Flipper at the Life Lexicon
Forum threads
- Oscillator Discussion Thread (discussion thread) at the ConwayLife.com forums
- Smallest Known Oscillators to p106 (and Beyond) (discussion thread) at the ConwayLife.com forums
- First Known Oscillators for Each Period (discussion thread) at the ConwayLife.com forums